Increased genotypic diversity has been associated with increased biomass production in short‐rotation tree species. Increasing the genotypic diversity of loblolly pine (Pinus taeda L.) in an attempt to increase productivity has not been extensively studied nor tested operationally or over long durations (i.e., >7 yr). We used genetically mixed and pure rows of loblolly pine growing throughout its planted range—Virginia, North Carolina, and Brazil—to test the effects of genetic mixing on volume production. There were no significant effects of mixing rows compared to pure rows on uniformity or mortality. Under intensive silviculture, individual trees planted in mixed rows had approximately 7% greater volume than those in the pure rows (estimate = 0.015 m³/tree ± 0.006) in the final year of measurement—year 8 for Brazil and year 10 for North Carolina and Virginia. Scaling the increase in individual stem volume under mixed rows and intensive silviculture to 1235 stems ha⁻¹ would equate to an additional 1.85 m³·ha⁻¹·yr⁻¹ in mean annual increment. Measuring the net biodiversity effect, our data suggest the positive growth response is driven by complementarity and not selection, meaning both genetic entries tend to grow larger when grown together. Additional trials are necessary to test the effects of mixing rows across large plots and to assess whether this increase is sustained throughout the rotation. If this increasing trend were to hold for intensively managed plantations, strategically mixing rows to increase productivity could be a valuable addition to an intensively managed plantation requiring relatively little added operational consideration to implement.

中文翻译：

---

互补性提高了整个种植范围内火炬松（Pinus taeda L.）的遗传混合物的产量

基因型多样性的增加与短轮伐树种生物量生产的增加有关。试图提高生产力的火炬松（Pinus taeda L.）的基因型多样性尚未得到广泛研究，也未进行过长期或长期（即> 7年）的测试。我们使用遗传混合纯种的整棵火炬松生长在整个种植范围（弗吉尼亚州，北卡罗莱纳州和巴西），以测试遗传混合对批量生产的影响。与纯排相比，混合排对均匀性或死亡率没有显着影响。在集约化造林下，混合行中种植的单个树木的体积比纯行中的大约大7％（估计= 0.015 m ³/ tree±0.006）在测量的最后一年-巴西为8年，北卡罗来纳州和维吉尼亚为10年。在混合行和强化造林下，将单个茎的体积增加到1235个茎ha ^-1相当于增加了1.85 m ³ ·ha ^-1 ·yr ^-1平均每年递增。衡量生物多样性的净效应，我们的数据表明，积极的增长反应是由互补性而不是选择驱动的，这意味着两个遗传条目在一起生长时往往会变大。必须进行其他试验来测试大块土地上混合行的效果，并评估这种增加是否在整个轮换期间得以持续。如果对于集约化管理的种植园而言，这种增长趋势得以保持，那么战略性地混合行以提高生产力可能是集约化管理的种植园的宝贵补充，而集约化管理的种植园则需要相对较少的运营考虑。